Detection and Correction of Systematic Errors in Instrument Transformers Along With Line Parameter Estimation Using PMU Data

We consider the following two estimation problems from synchrophasor measurements: first, estimation of positive sequence transmission line parameters and second, estimation of ratio correction factors for instrument transformers (ITs), also known as remote meter calibration (RMC). These two seemingly distinct problems are actually interrelated because incorrect parameters of any one set adversely affects the results of another. Hence, a simultaneous line parameter and RMC approach is proposed. Following extensions and adaptions viz., implicit RMC, explicit RMC, solving an individual line problem, and solving a network level problem are proposed. Open-circuit tests on transmission lines are proposed to improve accuracy in RMC. A decibel-scale-based statistical score is introduced for detection of ITs which require calibration. Extensive simulation results are presented to justify the claims.